Considerations in prophylaxis for tumor-associated epilepsy: Prevention of status epilepticus and tolerability of newer generation AEDs

ObjectiveTo identify risk factors for the development of tumor-associated epilepsy (TAE) and potential benefit of newer generation AEDs in seizure prevention.MethodsWe performed an IRB approved retrospective study of newly diagnosed GBM patients at the University of Rochester between 1/1/05 and 5/13/11. Records were reviewed to describe demographics, seizure incidence, occurrence of status epilepticus, and AED use and toxicity.Results172 patients with newly diagnosed GBM were included in the study. 53.4% developed TAE. 31.4% had seizure prior to diagnosis. 118 patients were seizure-free at diagnosis: 32.2% developed post-diagnosis TIE (PostTAE) and 60.2% remained seizure-free. 70 seizure-free patients received an AED peri-operatively. 36 were weaned off AEDs and 31 were continued. Incidence of PostTAE and time to first seizure were comparable in AED-treated and untreated patients. 4 PostTAE patients presented with status epilepticus (SE), all were not AED treated. AEDs were withdrawn in 10 patients due to toxicity: 9 from phenytoin and 1 from levetiracetam.ConclusionThere is a high incidence of PostTAE in GBM. Prophylactic AED therapy did not reduce PostTAE but may have prevented SE. Minimal toxicity was observed on 2nd generation AEDs. The high burden of epilepsy in this population and tolerability of newer AEDS suggest that AAN guidelines should be revisited.